Preferred Language
Articles
/
alkej-333
Active Vibration Suppression of Smart Cantilever Beam with Sliding Mode Observer Using Two Piezoelectric Patches
...Show More Authors

This paper presents a vibration suppression control design of cantilever beam using two piezoelectric ‎patches. One patch was used as ‎an actuator element, while the other was used as a sensor. The controller design was designed via the balance realization reduction method to elect the reduced order model that is most controllable and observable. ‎the sliding mode observer was designed to estimate six states from the reduced order model but three states are only used in the control law. Estimating a number of states larger than that used is in order to increase the estimation accuracy. Moreover, the state ‎estimation error is proved bounded. An ‎optimal LQR controller is designed then using the ‎estimated states with the sliding mode observer, to ‎suppress the vibration of a smart cantilever ‎beam via the piezoelectric elements. The control spillover problem was avoided, by deriving an avoidance ‎condition, to ensure the ‎asymptotic stability for the proposed vibration ‎control design. ‎The numerical simulations were achieved to ‎test the vibration attenuation ability of the ‎proposed optimal control. For 15 mm initial tip ‎displacement, the piezoelectric actuator found ‎able to reduce the tip displacement to about 0.1 ‎mm after 4s, while it was 1.5 mm in the ‎open loop case.  The current experimental results showed a good performance of the proposed LQR control law and the sliding mode observer, as well a good agreement with theoretical results.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Dec 01 2008
Journal Name
Journal Of Economics And Administrative Sciences
استخدام البرمجة الديناميكية في حل انموذج المعاينة الدورية الثابته لمشكلة الخزين مع تطبيق عملي في شركة الاقصى التجارية لاستيراد المولدات
...Show More Authors

The purpose of this paper is use the Dynamic Programming to solve a deterministic periodic review model for inventory problem and then to find the optimal policies that the company must uses in the purchase or production  (in the practical application example the Al Aksa company purchase the generators from out side country).

 

View Publication Preview PDF
Crossref
Publication Date
Sat Dec 31 2022
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
SYNTHESIS AND CHARACTERIZATION OF NEW DEMULSIFIER FROM NATURAL AND SYNTHETIC POLYMER: SYNTHESIS AND CHARACTERIZATION OF NEW DEMULSIFIER FROM NATURAL AND SYNTHETIC POLYMER
...Show More Authors

ABSTRACT

This research included the preparation and characterization of new demulsifies from natural and synthetic polymers of chitosan and polyvinyl alcohol that are environmentally friendly and at the same time have high efficacy comparable to emulsifiers. imported foreign. The prepared compounds were examined using infrared spectroscopy and nuclear magnetic resonance spectroscopy, and all the spectral signals of the polymers were in good agreement with the chemical composition of the polymers. And the melting and decomposition that occur on polymers at high temperatures. The effect of the length and type of side chain in the compositions of polymers on the process of water separation of oil emulsions w

... Show More
View Publication Preview PDF
Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Restrained Edges Effect on the Dynamics of Thermoelastic Plates under Different End Conditions
...Show More Authors

Frequency equations for rectangular plate model with and without the thermoelastic effect for the cases are: all edges are simply supported, all edges are clamped and two opposite edges are clamped others are simply supported.   These were obtained through direct method for simply supported ends using Hamilton’s principle with minimizing Ritz method to total energy (strain and kinetic) for the rest of the boundary conditions. The effect of restraining edges on the frequency and mode shape has been considered. Distributions temperatures have been considered as a uniform temperature the effect of developed thermal stresses due to restrictions of ends conditions on vibration characteristics   of a plate with different

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
Biosynthesis, characterization, and applications of aluminum oxide nanoparticles using aqueous extract of Cinnamon
...Show More Authors

View Publication Preview PDF
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
Classification & Evaluation of Evidence of deprivation in Iraq (2009) by using Cluster analysis
...Show More Authors

       The study aimed to reach the best rating for the views and variables in the totals characterized by qualities and characteristics common within each group and distinguish them from aggregates other for the purpose of distinguishing between Iraqi provinces which suffer from deprivation, for the purpose of identifying the status of those provinces in the early allowing interested parties and regulators to intervene to take appropriate corrective action in a timely manner. Style has been used cluster analysis Cluster analysis to reach the best rating to those totals from the provinces that suffer from problems, where the provinces were classified, based on the variables (Edu

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Aug 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The importance of using analytical procedures in the detection of creative accounting practices
...Show More Authors

The research aims to identify the importance of using analytical procedures in the detection of creative accounting practices. To achieve this goal, (100) questionnaires were prepared and distributed to the auditors in the Federal Financial Supervision Bureau and the authorized auditors' offices and practitioners of the auditing profession in Iraq. For the purpose of testing the research hypothesis and analyzing data, some appropriate statistical methods have been used and the use of the statistical program (SPSS) to analyze the data. The results of the research showed that the analytical procedures and tests applied by the auditor have a role in revealing and limiting creative accounting practices and methods and that auditors u

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Feb 01 2016
Journal Name
Journal Of Engineering
Valuation of Construction Projects Based on of Quantity Scale by using Expert System
...Show More Authors

The subject of an valuation of quality of construction projects is one of the topics which it becomes necessary of the absence of the quantity standards in measuring the control works and the quality valuation standards in constructional projects. In the time being it depends on the experience of the workers which leads to an apparent differences in the valuation.

The idea of this research came to put the standards to evaluate the quality of the projects in a special system depending on quantity scale nor quality specifying in order to prepare an expert system “ Crystal “ to apply this special system to able the engineers to valuate the quality of their projects easily and in more accurate ways.

View Publication Preview PDF
Publication Date
Sun Jul 01 2012
Journal Name
Baghdad University College Of Education Ibn Al-haitham
Numerical Solution of Linear System of Fredholm Integral Equations Using Haar Wavelet Method
...Show More Authors

The aim of this paper is to present the numerical method for solving linear system of Fredholm integral equations, based on the Haar wavelet approach. Many test problems, for which the exact solution is known, are considered. Compare the results of suggested method with the results of another method (Trapezoidal method). Algorithm and program is written by Matlab vergion 7.

View Publication
Publication Date
Sat Feb 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Environmental assessment of land use in the city of Samawah using spatial techniques
...Show More Authors
Abstract<p>The city of Samawah is one of the most important cities which emerged in the poverty area within the poverty map produced by the Ministry of Planning, despite being an important provincial centre. Although it has great development potentials, it was neglected for more than 50 years,. This dereliction has caused a series of negative accumulations at the urban levels (environmental, social and economic). Therefore, the basic idea of this research is to detect part of these challenges that are preventing growth and development of the city. The methodology of the research is to extrapolate the reality with the analysis of the results, data and environmental impact assessment of the projec</p> ... Show More
View Publication
Scopus (4)
Scopus Clarivate Crossref
Publication Date
Sun Feb 17 2019
Journal Name
Iraqi Journal Of Physics
A Study of the electronic structure of CdS Nanocrystals using density functional theory
...Show More Authors

Density Functional Theory at the generalized-gradient approximation level coupled with large unit cell method is used to simulate the electronic structure of (II-VI) zinc-blende cadmium sulfide nanocrystals that have dimensions 2-2.5 nm. The calculated properties include lattice constant, conduction and valence bands width, energy of the highest occupied orbital, energy of the lowest unoccupied orbital, energy gap, density of states etc. Results show that lattice constant and energy gap converge to definite values. However, highest occupied orbital, lowest unoccupied orbital fluctuates indefinitely depending on the shape of the nanocrystal.

View Publication Preview PDF
Crossref